226 LICHENACET. [PLATYSMA. 
t. 1606. Lichenoides endivic foliis crispis splendentibus, subtus 
nigricantibus Dill, Muse. 192, t. 25. f. 96.—Brit. Exs.: Mudd, 
n, 54; Leight. n. 44; Bohl. n. 79, 
The thallus often spreads extensively over the substratum to the ex- 
clusion of all other lichens. It varies in colour from ivory-white above 
to pitch-black beneath, and also in the length and breadth of the laciniee ; 
when more depressed it is often somewhat parmelioid. The apothecia, 
which in old plants become large and deformed, are rare in this country ; 
nor ere the spermogones very common, at Jeast in dried specimens, They 
are papilloso-tuberculose, with sterigmata 2-4-articulate, and spermatia 
about 0,007 mm. long, 0,001 mm. thick. 
Hab. On trunks of trees, walls, rocks, and on the ground, in upland 
and subalpine localities.—Distr. General and usually plentiful in the 
mountainous tracts of Great Britain; very abundant and luxuriant in the 
Central Highlands of Scotland; not very frequent in Ireland ; rare in the 
Channel Islands.—B. M.: Boulay Bay, Island of Jersey. Near Sprous- 
ton and at Sall, Norfolk; High Beech, alee Forest, Essex ; New Forest, 
Hants; Hay Tor and Lustleigh Cleeve, Dartmoor, Devonshire ; Lamorna 
and Helminton, Cornwall; Charnwood Forest and Gopsall Park, Leices- 
tershire; near Matiock, Derbyshire; Craigforda near Oswestry, Shrop- 
shire; near Barmouth, and Dolgelly, Merioneth; Island of Anglesea; 
Kildale Moor, Cleveland, Yorkshire; Teesdale and Cronkley Fell, Durham; 
Stavely Head, Westmoreland; Ashgill, Cumberland. New Galloway, 
Kirkcudbrightshire ; near Loch Skene, Moffat, Dumfriesshire ; Pentland 
Hills and Swanston Wood, near Edinburgh; near Inverary and Loch 
Creran, Argyleshire; Killin, Ben Lawers, Loch Earn, and Birnam Hill, 
Dunkeld, Perthshire ; Deerhill Wood, Forfarshire ; Countesswells Wood, 
near Aberdeen; Glen Callater and Lion’s Face, Braemar; near Forres, 
Elginshire; Glen Nevis and Loch Ennich, Inverness-shire; Hills ot 
Applecross, Ross-shire. Killarney, Lough Brui and Finnchey Bridge, 
co. Kerry. 
Form 1. fallax Nyl. Syn. i. (1860) p. 314.—Thallus cither 
whitish maculate or almost entirely whitish beneath, the laciniz 
often more or less dissecto-fimbriate at the margins. Apothecia as 
in the type.—Cromb. Lich. Brit. p. 27 ; Leight. Lich. Fl. p. 103, ed. 3, 
p. 98.—Cetraria glauca 8. fallaa Hook. F1. Scot. ii. p. 57 ; Sm. Eng. 
Fi. v. p. 220; Mudd, Man. p. 80. Lrchen fallax Web. Spicil. Fl. 
Germ. (1778) p. 244; Dicks. Crypt. fase. i. p. 13.; With. Arr. ed. 3, 
iv. p.53; Eng. Bot. t. 2373. Lichenoides membranaceum, tube Fallo- 
piance emulum Dill. Muse. 165, t. 22. f. 58.—Brit, Hxs.: Mudd, n. 55. 
Distinguished by the colour of the under surface of the thallus, which is 
sometimes variegated with black and white, and at other times is almost 
entirely whitish. With us it is very rarely fertile, the state in which 
the lacinie are dissecto-fimbriate (coralloidea Wallr., Leight. Lich. Fl. 
Ul. c.) being here as elsewhere always sterile. 
Hab. On the trunks of old trees in shady woods, rarely on moist rocks, 
in upland districts — Distr. Rather local and scarce in 8., W., and N. Eng- 
land, in Central Scotland, and in 8.W. Ireland.—B. M.: Dartmoor, 
Devonshire; Helminton, Cornwall; Garth, Dolgelly, Merionzthshire ; 
Ingleby Park, Cleveland, Yorkshire. Near Inverary, Argyleshire ; Glen 
Falloch, Finlarig, Killin, Perthshire; Sidlaw Hills, Forfarshire; Glen 
Nevis, Lochaber, Inverness-shire. 
